The Asymmetry Observed between the Effects of Photon-Phonon Coupling and Crystal Field on the Fine Structure of Fluorescence and Spontaneous Four-Wave Mixing in Ion-Doped Microcrystals.

In this paper, we explore the asymmetry observed between the effects of photon-phonon coupling (nested-dressing) and a crystal field (CF) on the fine structure of fluorescence (FL) and spontaneous four-wave mixing (SFWM) in Eu3+: BiPO4 and Eu3+: NaYF4. The competition between the CF and the strong photon-phonon dressing leads to dynamic splitting in two directions. The CF leads to static splitting in one direction under weak phonon dressing. The evolution from strong dressing to weak dressing results in spectral asymmetry. This spectral asymmetry includes out-of-phase FL and in-phase SFWM. Further, the large ratio between the dressing Rabi frequency and the de-phase rate leads to strong FL and SFWM asymmetry due to photon-phonon constructive dressing. Moreover, the experimental results suggest the analogy of a spectra asymmetry router with a channel equalization ratio of 96.6%.

Postoperative screw pullout of severe spondylolisthesis in osteogenesis imperfecta: a case report with 3-year follow-up.

Introduction and importance: Osteogenesis imperfecta (OI) is a rare skeletal disorder characterized by bone fragility and deformities in both paediatric and adult populations. The occurrence of severe spondylolisthesis in OI patients is even more infrequent. However, there is no consensus regarding the optimal treatment approach for OI patients afflicted with severe spondylolisthesis. The selection of surgical procedures and the effective management of postoperative complications present significant challenges in this context. Case presentation: A 30-year-old male patient diagnosed with OI type IV (Sillence classification) underwent the lumbar laminectomy and postero-lateral fusion due to severe spondylolisthesis (grade Ⅲ). Following the surgery, the patient experienced postoperative screw pullout while on bedrest. However, aside from experiencing back pain, there were no neurological symptoms present. To address this issue, the patient received salvage treatment in the form of cast immobilization combined with bisphosphonates. At the 3-year follow-up, the patient exhibited absence of sciatic nerve pain and reported mild numbness in the lower extremities. Moreover, the patient demonstrated the ability to ambulate a distance exceeding 1500 m. Nevertheless, the persistence of sexual dysfunction was observed. Clinical discussion: This study presented the initial instance of surgical complications observed in patients with severe spondylolisthesis and OI. This highlights the importance to exercise meticulous caution and thoroughness when assessing surgical interventions. Conclusion: In cases where the fixation fails to offer adequate biomechanical stability, the administration of bisphosphonates and robust immobilization remains crucial, even in the presence of complications.

Identifying the Interfacial Polarization in Non-stoichiometric Lead-Free Perovskites by Defect Engineering.

Recent advances in perovskite ferroelectrics have fostered a host of exciting sensors and actuators. Defect engineering provides critical control of the performance of ferroelectric materials, especially lead-free ones. However, it remains a challenge to quantitatively study the concentration of defects due to the complexity of measurement techniques. Here, a feasible approach to analyzing the A-site defect and electron in alkali metal niobate is demonstrated. The theoretical relationships among defect concentration, conductivity, and oxygen partial pressure can be established based on the defect chemistry equilibria. The type and concentration of defects are reflected through the conductivity variation with oxygen partial pressure. As a result, the variation of defect concentration gives rise to defect-driven interfacial polarization, which further leads to distinct properties of the ceramics. e.g., abnormal dielectric behavior. Furthermore, this study also suggests a strategy to manipulate defects and charges in perovskite oxides for performance optimization.

Enhanced NO2 Sensing Performance of ZnO-SnO2 Heterojunction Derived from Metal-Organic Frameworks.

Nitrogen dioxide (NO2) is the major reason for acid rain and respiratory illness in humans. Therefore, rapid, portable, and effective detection of NO2 is essential. Herein, a novel and simple method to construct a ZnO-SnO2 heterojunction is fabricated by pyrolysis of bimetallic metal organic frameworks. The sensitivity of ZnO-SnO2 heterojunction towards 0.2 ppm NO2 under 180 °C is 37, which is 3 times that of pure ZnO and SnO2. The construction of heterojunction speeds up the response-recovery process, and this kind of material exhibits lower detection limit. The construction of heterojunction can significantly improve the NO2 sensitivity. The selectivity, stability, and moisture resistance of ZnO-SnO2 heterojunction are carried out. This could enable the realization of highly selective and sensitive portable detection of NO2.

Enhancing Li-Ion Transport in Solid Electrolytes by Confined Water.

Developing new oxide solid electrolytes with fast Li-ion transport and high stability is an important step to realize high-performance solid-state Li-ion batteries. Hydrate materials containing confined water widely exist in nature or can be easily synthesized. However, they have seldom been explored as Li-ion solid electrolytes due to the stereotype that the presence of water limits the electrochemical stability window of a solid electrolyte. In this work, it is demonstrated that confined water can enhance Li-ion transport while not compromising the stability window of solid electrolytes using Li-H-Ti-O quaternary compounds as an example system. Three Li-H-Ti-O quaternary compounds containing different amounts of confined water are synthesized, and their ionic conductivity and electrochemical stability are compared. The compound containing structural pseudo-water is demonstrated to have an ionic conductivity that is 2-3 order of magnitude higher than the water-free Li4 Ti5 O12 and similar stability window. A solid-state battery is made with this new compound as the solid electrolyte, and good rate and cycling performance are achieved, which demonstrates the promise of using such confined-water-containing compounds as Li-ion solid electrolytes. The knowledge and insights gained in this work open a new direction for designing solid electrolytes for future solid-state Li-ion batteries. Broadly, by confining water into solid crystal structures, new design freedoms for tailing the properties of ceramic materials are introduced, which creates new opportunities in designing novel materials to address critical problems in various engineering fields.

MoS2-Coupled Carbon Nanosheets Encapsulated on Sodium Titanate Nanowires as Super-Durable Anode Material for Sodium-Ion Batteries.

There is an ever-increasing demand for rechargeable batteries with fast charging, long cycling, high safety, and low cost in new energy storage systems. Herein, a heterogeneous architecture composed of MoS2-coupled carbon nanosheets encapsulated on sodium titanate nanowires is developed and demonstrated as an advanced anode for sodium-ion batteries (SIBs). Owing to the synergistic effects of ultrastable substrate of 1D sodium titanate (NTO) nanowires, high-capacity promoter of 2D MoS2 nanosheets as well as the 2D conductive carbon matrix, the resulting 1D/2D-2D hybrid demonstrates excellent high-rate capacity and super-durable cyclability, delivering a stable capacity of up to 425.5 mAh g-1 at 200 mA g-1. Even at an ultrafast charging/discharging process within 80 s, the capacity can be maintained at 201 mAh g-1 after 16 000 cycles with only 0.0012% capacity loss per cycle, one of the best high-rate capacities and cyclabilities for NTO-based hybrid composites. The present work highlights the designing protocol of hierarchical nanoarchitectures with stable substrate and high-capacity electrodes for next-generation energy storage applications.

Lithium titanate hydrates with superfast and stable cycling in lithium ion batteries.

Lithium titanate and titanium dioxide are two best-known high-performance electrodes that can cycle around 10,000 times in aprotic lithium ion electrolytes. Here we show there exists more lithium titanate hydrates with superfast and stable cycling. That is, water promotes structural diversity and nanostructuring of compounds, but does not necessarily degrade electrochemical cycling stability or performance in aprotic electrolytes. As a lithium ion battery anode, our multi-phase lithium titanate hydrates show a specific capacity of about 130 mA h g-1 at ~35 C (fully charged within ~100 s) and sustain more than 10,000 cycles with capacity fade of only 0.001% per cycle. In situ synchrotron diffraction reveals no 2-phase transformations, but a single solid-solution behavior during battery cycling. So instead of just a nanostructured intermediate to be calcined, lithium titanate hydrates can be the desirable final destination.Water is usually not favorable in high-voltage window aprotic electrolytes. Here the authors discover some lithium titanate hydrates that allow superior power rate and ultralong cycle life in aprotic electrolytes.

Efficient Lithium-Ion Storage by Hierarchical Core-Shell TiO2 Nanowires Decorated with MoO2 Quantum Dots Encapsulated in Carbon Nanosheets.

Rational design and surface engineering are the key to synthesizing high-performance electrode materials for electrocatalysis and energy conversion and storage applications. Herein, a novel three-dimensional (3D) nanoarchitecture of TiO2 nanowires decorated with MoO2 quantum dots encapsulated in carbon nanosheets was successfully synthesized by a simple polymerization method. Such a hierarchical nanostructure can not only exhibit the synergistic effect of structural stability of a 1D TiO2 substrate and high capacity of 0D MoO2 quantum dots but also prevent the aggregation and oxidation of MoO2. As a result, the novel 0D-1D-2D composite illustrates an initial discharge capacity of 470 mAh g-1 at a high current density of 500 mA g-1, especially a capacity retention of about 83% after 450 cycles. The present work highlights the designing strategy of nanoarchitectures containing high capacity materials for enhancing electrochemical performance of Ti-based materials.